Knife grinder



Nov." 6, 1934. F. w. SEYBOLD KNIFE GRINDER 4 Sheets-Sheet 1 Filed April 25, 1933 fkspzelck M Jiyemn HI JLLL &

v w |-l 1 ATTORNEY:

Nov. 6, 1934. F. w. SEYBOLD KNIFE GRINDER Filed April 25, 1935 4 Sheets-Sheet 2 illll F. w. SEYBOLD 1,979,775

KNIFE GRINDER Filed April 25, 1933 1' 95 97 I 92 101 104 101 z? I! 91,

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KNIFE GRINDER Filed April 25, 1935 4 Sheets-Sheet 4 mum/m a 27 (W Mil Patented Nov. 6, 1934 FFEQE KNIFE GRINDER Frederick W. Seybold, Dayton, Ohio, assignor to Harris, Seybold, Potter Company, Cleveland, Ohio, a corporation of Delaware Application April 25, 1933, Serial No. 667,841

9 Claims.

This invention relates to improvements in knife grinders, that is to say machines for grinding the cutting edges of knives such as are used in paper cutting machines, chipper and rag knives for paper mills, tobacco knives, doctor blades, shear blades, etc.

In grinding machines for the purpose stated, as usually constructed, the grinding wheel is mounted in a fixed position and the blade to be ground is caused to move back and forth longitudinally past the grinding wheel. This requires a parallel feeding movement of the ends of the knife toward the wheel, and any back-lash or slippage in the mechanism throws the knife bar out of parallel. Furthermore in such machines, wherein there is a traversing knife bar, the required floor space is much greater than the length of the knife bar. Then too, the knife bar overhangs the machine frame when in either extreme position, and drippage of cooling liquid necessarily occurs.

One of the objects of my invention is the provision of a knife grinding machine of the type wherein the knife bar is stationary, and the grinding wheel is mounted upon a traveling carriage.

Another object is the provision of a rigid type of machine, without overhang, occupying a floor space only slightly longer than the length of the knife bar.

Another object is the provision of a machine wherein the grinding wheel is fed toward the knife, the latter remaining rigid, thereby insuring that the grinding will remain parallel with each succeeding pass.

Another object is the provision of a machine in which all of the moving parts are mounted upon the traversing unit, whereby a single unit may be manufactured for use upon machines of different lengths.

A further object is the provision of a knife bar having a plurality of knife supporting surfaces arranged for convenience in carrying knives having long bevels or short bevels, the knife bar being rotatable for accurate angle adjustment and for convenience in mounting and demounting the knives.

Still another object is the provision of a novel and simple multiple segment grinding wheel.

Other objects and features of novelty will appear as I proceed with the description of that embodiment of the invention which, for the purposes of the present application, I have illustrated in the accompanying drawings, in which Figure 1 is a side elevational view of a grinding machine embodying the invention.

Fig. 2 is an end View of the same.

Fig. 3 is a detail horizontal sectional view taken substantially on the line 33 of Fig. 2.

Fig. 4 is a vertical sectional view of the means for feeding the grinding wheel toward the work, the view being taken substantially on the line 4-4 of Fig. 2.

Fig. 5 is a front view of the segmental grinding wheel.

Fig. 6 is a cross section of the grinding wheel taken substantially on the line 6--6 of Fig. 5.

Fig. '7 is a vertical cross sectional detail view of the traversing mechanism, this view being taken substantially on the line 7-7 of Fig. 2.

Fig. 8 is a detail end elevation of the knife bar with a very short bevel blade mounted thereon.

Fig. 9 is a similar view with the knife bar set at a different angle and supporting a blade with a longer bevel.

Fig. 10 is a fragmental sectional view of the knife clamping means of Fig. 9, the view bein taken on the line 10-10 of Fig. 9.

Fig. 11 is a view similar to Figs. 8 and 9, showing still another position of the knife bar, and with a knife thereon of less Width than the knife. 30 of Fig. 9, and

Fig. 12 is a diagrammatic end view of the machine, showing a water circulating means which I may employ.

The machine may have a cast metal or other 5 rigid bed 10, provided with a V-way 11 and a fiat way 12. At the ends of the bed standards 13 are mounted upon or attached to the bed. In order to insure accurate alignment the standards may be provided with V-shaped projections 1 machined to fit accurately within the machined way 11. These standards have mounted therein, parallel to the way 11, a stationary-lead screw 15. The standards also carry split bearings 16 within which there is rotatably mounted the cylindrical ends of a knife bar 17. The split bearings 16 may be loosened or tightened by the manipulation of nuts 18 having handles 18', these nuts being threaded upon studs 19. Near One extremity the knife bar 17 has attached thereto a worm wheel 20, with which meshes a worm 21 upon a short shaft 22 carried in a bracket 23 upon the adjacent standard 13. On the outer extremity of the shaft 22 there is a hand wheel 24. When the nuts 18 are loosened, the wheel 24 may be rotated to turn the knife bar 17 in its bearings to whatever degree is necessary or desired.

The knife bar is preferably provided with several knife supporting surfaces. In the embodiment herein illustrated I have shown three such surfaces, numbered 25, 26 and 27 respectively, see particularly Figs. 8, 9 and 11. In Fig. 8 a doctor blade 28 is shown mounted on the surface 25 b means of a series of clamping fingers 29 working against aspacing bar 30, and held in place by a series of bolts or studs 31. It is to be understood that the clamps 29 are positioned at intervals along the length of the blade 28.

In Figs. 9 and 10 a cutter blade 32 is mounted against the surface 26 of the knife bar by means of a clamp 29 at each end of the blade workin against the spacing plate or block 33, the clamp being held in operative position by a bolt or stud 34 threaded into the knife bar.

In the case of Fig. 11 a cutter blade 35 oflsomewhat sharper bevel and less width is mounted against the surface'27 of the knife bar, being secured in place, as before, by a series of clamps 29 working against a spacing plate 36, and held in place by bolts or studs 37.

It will be noted that thesurface 26 is wider than the surface 27 and can thus accommodate a knife of greater width than the knife 35. Any precise angle of bevel can be obtained by rotation of the knife. bar by means of the wheel 24. A

pointer 38 in connection with gauge marks on the the machine, including an electric motor 40 which is mounted upon an extension 41 of the carriage. The shaft 42 of the motor is on the same level with lead screw 15.

The upper end of the carriage 39 comprises a sleeve 43 within which is slidably mounted a barrel 44. This barrel, in an intermediate part of its length, is turneddown somewhat so as to clear the sleeve 43, and is there provided with screw threads 45. A threaded collar 46, with an extension in the form of a hand wheel, is mounted to turn upon the threads 45, being positioned between separated portions of the sleeve 43 so that when the collar 46 is rotated the barrel 44 is caused to move slightly inwardly or outwardly in the sleeve 43. In the barrel 43 I mount upon roller bearings or the like 47 and 48 a shaft 49, to the forward end of which the grinding wheel is secured. On the rear end of the shaft 49 there are two pulleys 52, which are slidably keyed to the shaft so that the pulleys may remain in a given position while the shaft moves with the barrel 44. These pulleys 52 are driven by V-belts 53 running over V-pulleys 54 on the motor shaft 42.

The grinding wheel is of cup shape. It comprises a back member 54 which is centrally perforated to receive a constricted end of shaft 49. The wheel is fixed in position by means of a nut 55 threaded onto the reduced extremity of the shaft. The back member 54 is circular, and approximately flat, except that it is provided on its forward side with an annular segment supporting member 56. The outer surface of this supporting member is inclined inwardly toward the back member 54, as shown at 57. At regular intervals the supporting member 56 is provided with threaded perforations 58, into which are threaded screws 59 that extend through smooth bores in wedges 60. The inclined faces of these wedges engage similarly inclined faces on the ends of grinding segments 61 that rest at their rear ends upon the annular support 56. The inner surfaces of the segments 61 are enlarged at the rear ends of the segments, that portion of the inner surface of each segment being formed to complement the inclined surface 57 of the supporting member. Since the parts are circular, these inclined surfaces are in fact conical. The balance of the inner surface of each segment and all of the outer surface are preferably cylindrical, although this shape is not entirely essential, as the grinding operation is performed by the forward Side or edge of the segment, which is preferably fiat. When the segments 61 and wedges are all in place, the screws 59 may be screwed into the threaded openings 58 to tighten down the wedges, thereby not only drawing the segments radially inward, but also drawing them longitudinally rearward against the surface 62 of the back member 54. The surfaces 57 and 62 are machined for accuracy,.and hence the segments 61 are positioned by the wedges accurately as to circular alignment as well as to bring their grinding faces accurately up to the plane of grinding. The form of the grinding segment and the means employed for mounting and demounting it with facility and accuracy, constitute important features of my invention.

Referring now to the traversing means for the carriage, the lower part of this carriage consists primarily of a gear casing through which the lead screw 15 extends. Surrounding the lead screw there is a long nut 65, see particularly Fig. 7, the middle portion only of which is threaded to run upon the threads of the screw 15. This nut is held againstlongitudinal movement with respect to the carriage by a flange 66 at one end bearing against a side wall of the carriage, and at the other end by a pair of threaded collars 67 which bear against the other side wall of the carriage and may be removed when it is desired to disassemble the mechanism.

A clutch spool 68 is slidably keyed to this nut, the keyway being indicated at 69 in Fig. 7. Upon this spool there are a pair of cone clutch members 70and 71 which are adapted to engage with inner cone surfaces on two bevel gears 72 and 73 respectively. The latter gears have hubs 74 and 75 which are mounted rotatably in bushings 76 mounted in bearing bosses 7'7 and 78 formed in the walls of the carriage. The gears 72 and 73 are both driven constantly, in opposite directions, by a bevel pinion 79. The latter pinion is carried upon the end of a shaft 80 which is hollow and receives the motor shaft 42, with which it is in alignment and to which it is operatively connected. The shaft 80 is mounted in ball bearings 81 and 82. It will be apparent that when the clutch member 71 is in engagement with the gear 73, as shown in Fig. 7, rotation will be trammitted from that gear through spool 68 to nut 65, causing the nut to turn in a given direction and to be traversed along with the carriage lengthwise of the lead screw 15 in a given direction.

'When the clutch spool 68 is in an intermediate position neither one of the gears 72 and 73 drives the nut 75. When the spool is shifted however to cause clutch member 70 to engage the conical surface of gear 72, the rotation of the latter is transmitted to the nut 65 and the carriage is traversed in the opposite direction.

The shifting of the clutch spool is accomplished by a pair of blocks 84 which run in a groove in end against the lug 97.

the middle of spool 68, these blocks being carried upon a yoke which is fixed to a vertical pin 86 that is mounted to turn in bearings 87 and 88.

The arm 39 is a continuation of the yoke 85, and moves with it. This arm 89 has a pin 90 mounted therein and projecting upwardly therefrom. -t is also provided at its free extremity with an upwardly projecting pin 91. An operating lever 92 with a handle 93 projects out of the casing of the carriage 39 through a slot 94. This lever at its inner end is formed with an upwardly projecting box open at both ends, and its pivot is a headed pin 95 which is secured in the upper wall of the box portion. A perforated lug 97 extends upwardly from the lever 92 and slidably receives one end of a T-bar 98, the opposite end of which has a bore therein by means of which it is mounted upon the pin 91. A coil spring 99 surrounds this T-bar and bears at one The T-bar 98 and the coil spring 99 extend through the box portion of the lever. In the lower part of lever 92 there is an arcuate slot 100 which receives the pin 90.

The lever 92 also carries outside of the gear casing a pair of spaced depending lugs 101, within perforations of which there is slidably supported a rod 102 having a small anti-friction roller 103 at its inner end. The rod carries a collar 104. A coil spring 105 surrounds the rod and bears at one end against the collar 104 and at the other end against the outer lug 101, thereby tending to force the roller 103 toward a cam plate 106, which has a high central land, corresponding to neutral position of the clutch, and low points on either side corresponding to the two engaged portions of the clutch.

In Fig. 3 the arm 89 is shown shifted into position to cause clutch cone 71 to engage gear '73, corresponding therefore to Fig. 7. Now, when the outer end or" lever 92 is swung past the central position and down upon the other side of the central land of plate 106, the lug 97 is of course carried along with the lever. I The pin 90 in arm 39 is not at first affected, but when the movement of lever 92 is nearly completed, one end of slot 109 engages the pin 90 and shifts it past the line of centers of pin 86 and pivot 95, this line being marked C-C in Fig. 3 of the drawings. As soon as this occurs the spring 99 exerts its pressure to force the pin 91 over far enough to swing the arm 89 and the yoke 85 as far as they will go, in other words until the other clutch cone '70 engages the gear 72.

When it is desired to stop the traversing motion, the operator pulls the lever 92 into its interly engaged clutch cone from the clutch surface of the gear, and the traversing movement ceases.

The reversal of traversing movement may of course be accomplished by the operator swinging the handle 93 when the carriage approaches the end of its travel in either direction, but I prefer to make this action automatic by inserting limit pins 107 at proper places in a notched or perforated bar 108, which pins cause the motion of the carriage to swing the lever 92 at the proper times to accomplish the desired reversals. These pins may of course be set to correspond with the length of the blade being ground.

I have provided means for feeding the grinding wheel toward the work a definite amount for each complete reciprocation of the carriage. This I accomplish by forming serrations or ratchet teeth 109 in the periphery of the hand wheel 46 heretofore described, and employing a pawl 110 for engagement therewith. This pawl is mounted upon the short end of a lever 111, so that it is held against the ratchet by gravity. The lever 111 is pivotally mounted at 112 in a bifurcated post 113 which is fixed in the upper portion of the lever 92. It will be apparent from Fig. 4 that when the lever 92 is swung in one direction at one end of the carriage travel the pawl will merely ride over a series of teeth on the ratchet wheel, and that when the next or return swing of the lever 92 occurs, at the opposite end of the carriage travel, the pawl 110 will produce rotation of the ratchet wheel, and thereby cause the barrel 44, with its shaft 49 and the grinding wheel, to move toward the work a predetermined short distance.

When the operator desires to retract the grinding wheel the upper end of lever 111 is held in such position as to cause the pawl to disengage the ratchet teeth, when the wheel 46 may be rotated by hand in a reverse direction. If it is desired to regulate the feed of the grinding wheel by hand, the lever 111 may be swung inwardly toward the shaft 49 and secured in that position by any suitablefastening.

Beneath the knife bar I mount a long pan 114, within which the cooling liquid is stored, and to which it is returned after being used. In order j that spray may be reduced to a minimum, I employ a hood or cowl 115 which is supported upon the carriage and covers a considerable part of the upper portion of the grinding wheel, while a chute or drain plate 116, with side members substantially meeting the hood 115, directs any liquid which may be thrown from the wheel back into the pan 114.

Any suitable means may be employed for drawing water out of the pan 114 and playing it over the knife and wheel, but I prefer to use a pump 11'? of some suitable rotary type, the shaft of which carries a V-pulley 118 connected by a V- belt 119 with a V-pulley 120 attached to hollow shaft 80. The water or other cooling liquid discharged by the pump is carried through tubing 121, Fig. 12, to the point of contact between the blade 35 and the grinding wheel segments 61. The return or suction line for the pump is indicated at 122, being mounted upon and carried by the carriage, and terminating in the pan 114 near the bottom thereof.

The grinding wheel and its associated parts are mounted in a casting 123 which constitutes the upper part of the carriage 39. These two carriage parts are connected together partly by a pivot bolt 124 and partly by a stud 125 which extends through a short slot in the casting 123,

and is secured in a threaded hole in a lug formed 1 on the main part of the carriage 39. By loosening the stud 125, the casting 123 may be swiveled to a slight extent upon its pivot 124, so as to provide clearance for one side of the grinding wheel, and for the further purpose of providing more or less concavity in the ground surface of the knife. When the desired adjustment has been secured the screw 125 is again tightened.

In the foregoing description I have necessarily gone somewhat into detail in order to explain fully the particular embodiments of the invention herein illustrated, but I desire it to be understood that such detail disclosures are not to be construed as amounting to limitations, ex-

cept as they may be included in the appende claims.

Having thus described my invention I claim:

1. In a grinding machine, a pair of ways, end standards fixed with respect to said ways, an elongated work carrier mounted in said standards for rotational adjustment, a fixed lead screw mounted in said standards, a carriage slidable upon said ways, said carriage supporting an electric motor, a grinding wheel driven thereby, and a nut running upon said screw and driven by the motor for traversing the carriage upon its ways.

2. In a grinding machine, a pair of ways, end standards fixed with respect to said ways, an elongated work carrier mounted in said standards, an elongated pan beneath said carrier, means for traversing said carriage upon said ways, a grinding wheel mounted upon the carriage, said carriage also supporting a cooling fluid pump, a delivery connection from said pump to the point of contact between the grinding wheel and the work, a return connection to the pump movable with the carriage and extending into the pan, and means for driving said traversing means, said grinding wheel, and said pump.

3. In a grinding machine, a pair of ways, end standards fixed with respect to said ways, an elongated work carrier mounted in said standards, an elongated pan mounted beneath said work carrier, a fixed lead screw mounted in said standards, carriage slidable upon said ways, said carriage supporting an electric motor, a grinding wheel driven thereby, and a nut running upon said screw and driven by the motor for traversing the carriage upon its ways, said carriage also supporting a cooling fiuid pump, a delivery connection from said pump to the point of contact between the grinding wheel and the work, and a return connection to the pump movable with the carriage and extending into the pan.

l. In a grinding machine, a pair of ways, end standards fixed with respect to said ways, an elongated work carrier mounted in said standards, a fixed lead screw mounted in said standards, a carriage slidable upon said ways, an electric motor mounted upon the carriage, a grinding wheel mounted upon the carriage and operatively connected with said motor, a nut mounted upon the carriage and running upon said lead screw,

reverse gearing connections between said nut and motor, said connections comprising a pair of gears connected with said motor for rotation in opposite directions, clutch means for clutching either of said gears to said nut, and means automatically operable as the carriage approaches either end or" its travel for declutching one gear and clutching the other gear.

5. In a grinding machine, a pair of ways, end standards fixed with respect to said ways, an elongated work carrier mounted in said standards, a fixed lead screw mounted in said standards, a carriage slidable upon said ways, an electric motor mounted upon the carriage, a grinding wheel mounted upon the carriage and operatively connected with said motor, a nut mounted upon the carriage running upon said lead screw, reverse gearing connections between said nut and motor, said connections comprising a pair of gears connected with said motor for rotation in opposite directions, clutch means for clutching either of said gears to said nut, a lever for shifting said clutch means to disengage one clutch and engage the other clutch, and stops with which said lever engages as the carriage approaches either end of its travel.

6. In a grinding machine, a pair of ways, end standards fixed with respect to said ways, an elongated work carrier mounted in said standards, a fixed lead screw mounted in said standards, a carriage slidable upon said ways, an electric motor mounted upon the carriage, a grinding wheel mounted upon the carriage and operatively connected with said motor, pawl and ratchet means for feeding said wheel toward the work, a nut upon the carriage and running upon said lead screw, reverse gearing connections between said nut and motor, said connections comprising a pair of gears connected with said motor for rotation in opposite directions, clutch means for clutching either of said gears to said nut, a lever for shifting said clutch means to disengage one clutch and engage the other clutch, stops with which said lever engages as the carriage approaches either end of its travel, the pawl of said pawl and ratchet mechanism being mounted upon said lever.

'7. In a grinding machine, a pair of Ways, end standards fixed with respect to said ways, an elongated work carrier mounted in said standards, a carriage slidable upon said ways, a grindin wheel mounted upon the carriage, a ratchet wheel coaxial with said grinding wheel, means associated with the ratchet wheel for advancing the grinding wheel toward the work, mechanism for reciprocating the carriage on said ways and for reversin the direction of travel of the carriage at the ends of its stroke, said mechanism comprising a control element shifted by carriage movement underneath the ratchet wheel, and a pawl mounted on said control element engaging the ratchet wheel for returning the latter step by step.

8. In a grinding machine, a pair of ways, end standards fixed with respect to said ways, an elongated work carrier mounted in said standards, a carriage slidable upon said ways, a grinding wheel, a shaft for said grinding wheel arranged transversely of the carriage, a fixed lead screw parallel to the ways, a nut rotatable upon said screw and held against bodily movement with respect to the carriage, means for rotating said nut comprising a driving shaft mounted on the carriage parallel to said first named shaft, a motor mounted on the carriage with its shaft parallel to said previously mentioned shafts, and operative connections from said motor to both of said previously mentioned shafts.

9. In a grinding machine, a pair of ways, end standards fixed with respect to said ways, an elongated work carrier mounted in said standards, a carriage slidable upon said ways, a grinding wheel, a shaft for said grinding wheel arranged transversely of the carriage, a fixed lead screw parallel to the ways, a nut rotatable upon said screw and held against bodily movement with respect to the carriage, means for rotating said nut comprising a driving shaft mounted on the carriage parallel to said first named shaft, a motor mounted on the carriage with its shaft in alignment with and coupled to one of said previously mentioned shafts, and operative connections between said motor and the other of said previously mentioned shafts.

FREDERICK W. SEYBOLD. 

